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Diffstat (limited to 'internal/fusefrontend/file2_holes.go')
-rw-r--r--internal/fusefrontend/file2_holes.go68
1 files changed, 0 insertions, 68 deletions
diff --git a/internal/fusefrontend/file2_holes.go b/internal/fusefrontend/file2_holes.go
deleted file mode 100644
index 5c314d3..0000000
--- a/internal/fusefrontend/file2_holes.go
+++ /dev/null
@@ -1,68 +0,0 @@
-package fusefrontend
-
-// Helper functions for sparse files (files with holes)
-
-import (
- "context"
- "syscall"
-
- "github.com/hanwen/go-fuse/v2/fs"
-
- "github.com/rfjakob/gocryptfs/internal/tlog"
-)
-
-// Will a write to plaintext offset "targetOff" create a file hole in the
-// ciphertext? If yes, zero-pad the last ciphertext block.
-func (f *File2) writePadHole(targetOff int64) syscall.Errno {
- // Get the current file size.
- fi, err := f.fd.Stat()
- if err != nil {
- tlog.Warn.Printf("checkAndPadHole: Fstat failed: %v", err)
- return fs.ToErrno(err)
- }
- plainSize := f.contentEnc.CipherSizeToPlainSize(uint64(fi.Size()))
- // Appending a single byte to the file (equivalent to writing to
- // offset=plainSize) would write to "nextBlock".
- nextBlock := f.contentEnc.PlainOffToBlockNo(plainSize)
- // targetBlock is the block the user wants to write to.
- targetBlock := f.contentEnc.PlainOffToBlockNo(uint64(targetOff))
- // The write goes into an existing block or (if the last block was full)
- // starts a new one directly after the last block. Nothing to do.
- if targetBlock <= nextBlock {
- return 0
- }
- // The write goes past the next block. nextBlock has
- // to be zero-padded to the block boundary and (at least) nextBlock+1
- // will contain a file hole in the ciphertext.
- errno := f.zeroPad(plainSize)
- if errno != 0 {
- return errno
- }
- return 0
-}
-
-// Zero-pad the file of size plainSize to the next block boundary. This is a no-op
-// if the file is already block-aligned.
-func (f *File2) zeroPad(plainSize uint64) syscall.Errno {
- lastBlockLen := plainSize % f.contentEnc.PlainBS()
- if lastBlockLen == 0 {
- // Already block-aligned
- return 0
- }
- missing := f.contentEnc.PlainBS() - lastBlockLen
- pad := make([]byte, missing)
- tlog.Debug.Printf("zeroPad: Writing %d bytes\n", missing)
- _, errno := f.doWrite(pad, int64(plainSize))
- return errno
-}
-
-// Lseek - FUSE call.
-func (f *File2) Lseek(ctx context.Context, off uint64, whence uint32) (uint64, syscall.Errno) {
- cipherOff := f.rootNode.contentEnc.PlainSizeToCipherSize(off)
- newCipherOff, err := syscall.Seek(f.intFd(), int64(cipherOff), int(whence))
- if err != nil {
- return uint64(newCipherOff), fs.ToErrno(err)
- }
- newOff := f.contentEnc.CipherSizeToPlainSize(uint64(newCipherOff))
- return newOff, 0
-}